Hi, sorry for the double post, but need help on a catering issue.
Yesterday evening I had a guest text me to tell me that her and her husband have decided to be vegan and requested we changed their meal preference on the RSVP. The problem is that our caterer doesn't have a vegan option because they cook everything with butter. They said there's no way that they can accommodate this, because they can't verify with 100 percent certainty that items they serve don't touch animal products. They're so intense about it that they specify this in their prospective client brochure (which is true - they did). What should I tell the guests?
EDIT: I know it shouldn't matter, but when the invitations were initially sent out, these guests texted FH asking if the chicken was free range and the beef was grass fed. We said we weren't sure. I understand wanting to eat ethically, but they're really difficult.
UPDATED IN COMMENTS